With the rapid development of semiconductor fabrication technology, semiconductor devices now have higher device densities and higher integration degrees. As a type of basic semiconductor devices, transistors are widely used in various applications. Thus, as the increase of device densities and integration degrees, the transistors are becoming smaller and smaller.
Radio frequency (RF) chips are widely used in RF technology. In an RF chip, the product of the on-resistance (Ron) and the off-capacitance (Coff) of a transistor is often an important indication or criterion of the RF performance of the RF chip. A smaller product value often indicates a better RF performance.
For a transistor with a certain gate electrode size, the value of the on-resistance of the transistor is inversely proportional to the intensity of drain current. However, as the size of a transistor decreases, it becomes more difficult to increase the drain current of the transistor.